According to the last update info it's possible. I personally haven't looked into ti though. The weapon thing seems an issue of course and has possibly been missed by Lee when he added the latest lua commands. You could possibly get round it by loading the same character up with each weapon and then simply using the relevant npc, hiding the rest until they are needed. You would however have to rely on your own scripts or heavily modify the existing ones ,as at the moment if you set your npc to 3rd person there's no real way to swap back and forth afterwards.
Still, I can't say I've done more than give the new control script a cursory glance, it may be easier to change than I am thinking. I'm not keen on having to edit the FPE to alter anims though, and haven't seen an easy way to add more variety in this area. I spent ages searching for a pistol fire anim for instance. It seems there isn't one, or it's well hidden and I have missed it, so third person shooting feels pretty uninspiring and unrealistic for me. Take shooting again, when you aim up and down your character should angle their torso and arms to suit, again this does not happen and basically ruins the effect entirely. You would really need to be able to rotate limbs to achieve this, anims will not really cut it and I'm unsure at this point if you can do that on an animated object in GG.
Third person was definitely a rushed job and is nowhere near complete really. We will have to see what if anything happens in this area. Of course we have to wait awhile for the DX11 version to be hatched first
SPECS: Q6600 CPU. Nvidia 660GTX. 8 Gig Memory. Win 7.